For the majority of mollusks, the visible organic form has little importance in the life of the members of a species, since they cannot see one another and have, at most, only a vague perception of other individuals and of their surroundings. This does not prevent brightly colored stripings and forms which seem very beautiful to our eyes (as in many gastropod shells) from existing independently of any relationship to visibility.

The buried ocean on Saturn’s moon Enceladus seems to be stable across extremely long periods of time, making it an even more promising place to hunt for life